How important is the U.S. Senate race in Pennsylvania?

Single-candidate super PACs are dropping millions of dollars into the Keystone State, showing the magnitude to which high-profile congressional races have been nationalized.

For high-dollar donors, single-candidate groups present opportunities to shape the slate of candidates competing in what is expected to be a favorable year for Republicans.

An examination of Federal Election Commission filings shows that Honor Pennsylvania – the super PAC supporting GOP candidate David McCormick – has spent more than $15 million on the former CEO of hedge fund Bridgewater Associates. How much of that money came from Pennsylvanians?

None.

The Pennsylvania Conservative Fund, another McCormick supporter, raised $3.5 million against Mehmet Oz. Once again, none of the dollars came from PA.

American Leadership Action, a super PAC against McCormick, garnered $3.2 million of which 95 percent is out-of-state funding.

On the Democratic side, Penn Progress has raised $1.9 million for U.S. representative Conor Lamb. More than three-fifths of that amount came from outside Pennsylvania’s borders.

Axios reviewed 26 super PACs and totaled $84 million so far this cycle. More than three-fourths of that total came from donors who don’t reside in states where these groups are spending. And at least half of the 26 received at least 95 percent of their funding from out of state.

The Keystone State is not alone, although three of the top eight super PACs on the list favor either McCormick or Oz.

Saving Arizona and Protect Ohio Values — groups backing Republican Senate hopefuls Blake Masters and J.D. Vance, respectively— are funded almost entirely by a single out-of-state donor, California tech mogul Peter Thiel. Illinois industrial supply magnate Richard Uihlein is the sole donor to groups supporting Senate candidates Eric Greitens in Missouri and Jake Bequette in Arkansas. And Las Vegas casino magnate Steve Wynn is bankrolling Protect and Defend America, a PAC backing Republican Brady Duke’s Florida House bid.

Data: FEC; Chart: Sara Wise/Axios